<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div{
            display: flex;

            width: 100%;
            height: 200px;
            background-color: aquamarine;

            /* 主轴对齐方式 */
            justify-content: center;

            /* 侧轴多行对齐方式 */
            align-content: center;

            /* 侧轴单行对齐方式（项目间对齐方式） */
            align-items: center;

            /* 操作主轴 */
            /* flex-direction: column-reverse; */

            /* 控制换行 */
            /* flex-wrap: wrap; */

            /* 合写-操作主轴及控制换行 */
            flex-flow: row wrap; 
        }
        div span{
            width: 100px;
            height: 100px;
            background-color: blue;
            margin: 10px;
        }
        div span:nth-child(2){
            flex-grow: 2;
            flex-shrink: 0;
        }
        section{
            width: 100%;
            height: 200px;
            background-color: crimson;
            display: flex;
        }
        section div:nth-child(1){
            width: 200px;
            background-color: darkgoldenrod;
            flex-basis: 100px;
        }
        section div:nth-child(2){
            flex:1;
            background-color: darkseagreen;
            margin:0 10px;
        }
        section div:nth-child(3){
            width: 200px;
            background-color: darkgoldenrod;
        }
    </style>
    
</head>
<body>
    <div>
        <span>1</span>
        <span>2</span>
        <span>3</span>
        <span>4</span>
        <span>5</span>
    </div>
    <section>
        <div>1</div>
        <div>2</div>
        <div>3</div>
    </section>
</body>
</html>